Summary of Alden et al.’s “Cyber Security in the Quantum Era”

TO: Professor Ellis 

FROM: Lia Barbu

DATE: September 23, 2020

SUBJECT: 500-Word Summary

This memo is a 500-word summary of the article, “Cyber Security in the Quantum Era,” by Petros Alden and Elham Kashefi, both professors in the School of Informatics at the University of Edinburg. 

Cybersecurity is essential to protect our systems, and it should be ready for a new computational model as quantum technologies. Quantum theory was by far one of the significant technological developments of the 20th century. A breakthrough will be possible soon due to the research in the field. Quantum computers will be the most valuable quantum technology due to their computational power. Quantum technologies’ achievements already exist Google’s processor “Bristlecone” and satellite quantum communication.

Quantum computers are no longer a myth, and cybersecurity must prepare for this new era. Alden and Kashefi inform us, “Quantum technologies may have a negative effect to cybersecurity, when viewed as a resource for adversaries, but can also have a positive effect, when honest parties use these technologies to their advantage.” (Alden & Kashefi, 2019, p. 121). There are three scenarios: one everything is secure, and the other two explore what new challenges quantum technologies can create. In the first scenario, the honest party has classic technologies, and the adversary has a large quantum computer. In the second scenario, the honest party has limited access to quantum technologies, and the adversary can use any quantum technologies. The third scenario looks in the future: quantum computation devices and the parts implicated in the process would protect their data and be secure. The focus will be on quantum technology’s effects on cryptographic attacks and attacks on the new quantum hardware. 

Even though quantum attacks seem far away; there are three essential rationales why we must address it now: security can hit retroactively, to create secure cryptographic solutions, and to be ready to implement the new technology. Cybersecurity research in post-quantum cryptography is divided into three classes considering adversary use of quantum technology: classic technology with access to an oracle/quantum computer, modification of security definition, and changes required to the new protocol. There are cryptosystems considered secure to a quantum computer attack, and the article considers three issues: confidence, usability, and efficiency. Next is explained what can happen when the adversary can make changes to security notions and what steps should be taken to prevent and stop this action. Quantum rewinding is a technique that adds a mechanism that enforces malicious adversaries to behave as a weak one.

As quantum technologies develop, quantumly protocols should become a reality. Practicality includes research that includes quantum technologies presently achievable. Quantum gadgets open a door for new attacks like side-channels attacks. The security for this is the device-independence that comes with high resources cost. Standardization and protocols should be created for quantum technology. Quantum technology will become a significant part of the computing and communication environment. 


WALLDEN, P., & KASHEFI, E. (2019). Cyber security in the quantum era. Communications of the ACM62(4), 120–129.

Leave a Reply